Dr. Glenn Tagatz, a professor in the Marquette University education school, brought suit against Marquette under Title VII of the Civil Rights Act of 1964, as amended, 42 U.S.C. § 2000e
et seq.,
and the Age Discrimination in Employment Act of 1967, as amended, 29 U.S.C. § 626(c)(1). He charged that he had received smaller pay raises than colleagues who were either Catholic or under 40 years of age. Judge Warren, after a bench trial, entered judgment for Marquette,
The case is remarkable because, for the first time ever so far as we know, the plaintiff testified as his own expert witness. (We have found a case where a party’s employees testified as expert witnesses; the practice was criticized by the judge. See
Rust Engineering Co. v. Lawrence Pumps, Inc.,
Because the case was tried, the intricate issues concerning prima facie case that Dr. Tagatz presses on us are irrelevant.
United States Postal Service v. Aikens,
Marquette is a Jesuit institution. See
Maguire v. Marquette University,
Dr. Tagatz, who is 54 and an Episcopalian, received his doctorate in educational psychology from the University of Wisconsin and was hired by Marquette as an associate professor in 1968. In 1971 he was made chairman of the department of psychology in the education school but he was removed from that job in 1974. In 1976 he published a book that received a single, brutally unfavorable review, though the dean of the school of education said he rather liked it; since then Dr. Tagatz has published only one article in a professional journal. According to the Social Science Citation Index, Dr. Tagatz’s book has never been cited in a scholarly publication; and none of his articles has been cited since 1982. Compare
Weinstein v. University of Illinois,
Beginning in 1976 the dean placed annual raises on an explicitly meritocratic basis. Scholarly output (quality as well as quantity), teaching quality, and administrative and related service to the school or university are the criteria that the dean uses to determine how large a raise to give each member of the department. Between 1976 and 1981, Dr. Tagatz received average annual raises greater than some members of the department, but below the average. He brought this suit in 1982.
The evidence of discrimination is almost entirely statistical. It consists of a series of tables, prepared by Dr. Tagatz, that compare salary raises for Catholic and non-Catholic, over-40 and under-40 faculty members in the school of education. The samples are small, because the school of education has only a small faculty. In the table that Dr. Tagatz’s counsel told us at argument contained the strongest evidence for his client, the salary raises between 1975 and 1985 of each of the 28 faculty members were compared with the faculty member’s religion. The comparison showed that, on average, the Catholic members of the faculty received significantly larger annual raises than the non-Catholic ones. A similar table showed larger annual raises on a percentage basis for faculty members under 40 compared to those over 40. Marquette did not offer expert testimony, although Dr. Tagatz is incorrect to say that it offered no statistical evidence. It presented a table showing that the most productive scholars in the school of education, as measured by number of publications, happened to be Catholics. (Dr. Ta-gatz’s own conspicuous lack of scholarly productivity&emdash;attributed by the school’s dean to Dr. Tagatz’s having “gone on strike” after he was fired as department chairman&emdash;helped depress the average for the non-Catholic members of the depart- ment.) Another table presented by Mar- quette compared Dr. Tagatz’s numerical teaching evaluations with the average for the school’s faculty, and showed that in the six periods for which comparable data were available the average score was 57.02, but his score was only 53.07. There was testi- mony that in addition to being a below-av- erage teacher and at the bottom of the faculty in productivity, Dr. Tagatz was a poor citizen of the school&emdash;refusing an im- portant committee assignment, failing to go through proper channels, enlisting students in his vendettas against other faculty members (the practice so memorably described in Mary McCarthy’s novel The Groves of Academe), and generally behav- Groves of Academe), and generally behav *1044 ing in trying ways. Against this there was testimony that Dr. Tagatz is a prominent member of the department and leads it in the number and size of research grants received.
Dr. Tagatz's main argument is that if the plaintiff in a Title VII case presents evidence that passes standard tests of statistical significance, the defendant must present a statistically significant rebuttal or lose. This argument misunderstands the significance of statistical significance, both generally and in this case. One of Dr. Tagatz's tables comparing salary raises for Catholic and for non-Catholic faculty in the school of education reveals a difference (favoring the Catholics) that is significant at the .0048 level. This means (speaking very crudely-see Kruskal, Tests of Significance, in 2 Int'l Encyclopedia of Statistic 944, 957 (1978)) that there is a probability o less than 5 in 1,000 that the difference i due to chance. But to infer as Dr. Tagat would that there is a less than 5 in 1,00 chance (in the absence of contrary evidence that the group that received the highe raises was favored because it was compose of Catholics is erroneous. All that the dat show is that there is in all likelihood a real not a spurious, difference between th means of the samples compared. The dat do not show that the difference is due to a particular attribute (namely, being Catholic) which the members of the better-off group have and the members of the worse-oft group lack. Correlation is not causation. Ste. Marie v. Eastern R.R. Ass'n,
All this is not to say that Dr. Tagatz's tables are no evidence. Cf. MacDissi v. Valmont Industries, Inc.,
Dr. Tagatz objects very strongly lx Judge Warren's attempt to do a little statistical analysis of his own. One of Dr. Tagatz's tables compares the salary raises for the five Catholic and five non-Catholic faculty members who had been continuously employed since 1969, and shows that over this period the average salary raise for the Catholics was higher than for the non-Catholics (including Dr. Tagatz). All five Catholics were full professors at the end of the period, while only two of the non-Catholics were; and Judge Warren noted that if one compared the five Catholic full professors with the two non-Catholic full professors the latter group had done better. Dr. Tagatz points out correctly that a larger sample is more reliable than a smaller one, and complains that Judge Warren made an already very small sample`
*1045
significantly smaller by casting out three of its ten observations. "It is an unacceptable statistical procedure to turn a large sample into a small one by arbitrarily excluding observations." Washington v. Electrical Joint Apprenticeship & Training Comm., supra,
Judges, by the way, are not wallflowers or potted plants; and a district judge's effort to test the strength of a party's statistical evidence by determining how sensitive it is to the design of the sample-a standard method of evaluating statistical evidence-is rather to be commended than condemned. Compare Mister v. Illinois Central Gulf R.R.,
We have focused on the evidence of religious discrimination. The evidence of age discrimination was if anything less impressive. The discovery that young faculty members receive larger annual raises on a percentage basis is no evidence at all of age discrimination. As is well known, the professoriat, like the Roman Catholic hierarchy, has only a few ranks. And unlike the Catholic hierarchy, the top rank-full professor-is normally reached relatively early in the academic's career (Dr. Tagatz became a full professor in 1970, when he was 36). This rank structure implies, and one observes, that academics' salaries tend to rise rapidly in the early stages of their career and to reach a plateau when the academic becomes a full professor; and this regardless of age. The phenomenon of diminishing returns to years of experience is well documented in studies of academic salaries. See, e.g., Tuckman, et al., supra, at 697. Of course there are exceptions, but Dr. Tagatz's evidence was only of averages. It is unlikely-and there is no evidence-that the characteristic age profile of academic salaries reflects age discrimination. Among alternative explanations, tenure-and the job security that results from it-tends to take some of the edge off academic ambition. So we would expect tenured faculty to be somewhat less productive on average than nontenured faculty, and of course most nontenured faculty are under 40, and most faculty over 40 have tenure. A countervailing factor is that tenured faculty have passed a more careful screening process than untenured. A comparison not between a faculty member before and after he got tenure but between tenured and (different) nontenured faculty members might therefore reveal that tenured faculty were more productive. Cutting back the other way is the possibility that new faculty are more mobile than old-another reason why one might expect the new (who generally are younger) to receive higher raises. A further consideration is that tenure itself is a form of compensation, a substitute for money; this may be another reason why salary increases are higher on' a percentage basis for nontenured than for tenured faculty. Given plausible (we do not suggest compelling) explanations unrelated to age discrimination for the results of Dr. Ta-gatz's statistical comparisons, we can hardly say that Judge Warren committed a clear error in refusing to infer, from evidence unusually meager, that Marquette was discriminating against Dr. Tagatz because of his age.
Dr. Tagatz attempted to bolster his weak statistical evidence of religious and age discrimination with shards of testimonial evidence. There was testimony that the dean had suggested to one of the non-Catholic faculty members that she not wear her Masonic ring (the Catholic Church once regarded the Masons as dangerous heretics, and the Masons returned the com *1046 pliment); that he told the faculty that Catholic doctrine should be taught wherever possible; and that the younger members of the faculty were more productive than the older ones. Judge Warren was not required to give controlling weight to such evidence, especially since Dr. Tagatz teaches statistics and there is no suggestion that the dean wanted statistics taught with.a Catholic slant (e.g., regression of angels on the heads of pins).
Finally, Dr. Tagatz complains that Marquette discriminates in favor of Jesuit members of the faculty by giving them free housing and other (free) benefits. It is a nice question, not necessary to answer, whether discrimination in favor not of a religion but of a religious order is within the scope of Title VII. See
Pime v. Loyola University, supra,
Despite his use of the expert of his choice, Dr. Tagatz presented a weak case which was properly dismissed. Compare
Laborde v. Regents of University of California,
AFFIRMED.
